<template>
	<view class="chat">
		<scroll-view :style="{height: `${windowHeight-inputHeight}rpx`}" id="scrollview" scroll-y="true"
			:scroll-top="scrollTop" class="scroll-view">

			<!-- 聊天主体 -->
			<view id="msglistview" class="chat-body">
				<!-- 聊天记录 -->
				<view v-for="(item,index) in msgList" :key="index">
					<!-- 自己发的消息 -->
					<view class="item self" v-if="item.senderId == userId">
						<!-- 文字内容 -->
						<view class="content right">
							{{item.content}}
						</view>
						<!-- 头像 -->
						<view class="avatar">
							<img :src="item.userAvatar" alt="">
						</view>
					</view>
					<!-- 对方发的消息 -->
					<view class="item Ai" v-if="item.senderId == receiveId">
						<!-- 头像 -->
						<view class="avatar">
							<img :src="item.userAvatar" alt="">
						</view>
						<!-- 文字内容 -->
						<view class="content left">
							{{item.content}}
						</view>
					</view>
				</view>

			</view>
		</scroll-view>
		<!-- 底部消息发送栏 -->
		<!-- 用来占位，防止聊天消息被发送框遮挡 -->
		<view class="chat-bottom" :style="{height: `${inputHeight}rpx`}">
			<view class="send-msg" :style="{bottom:`${keyboardHeight}rpx`}">
				<view class="uni-textarea">
					<textarea v-model="chatMsg" maxlength="300" confirm-type="send" @confirm="handleSend"
						:show-confirm-bar="false" :adjust-position="false" @linechange="sendHeight" @focus="focus"
						@blur="blur" auto-height></textarea>
				</view>
				<button @click="handleSend" class="send-btn">发送</button>
			</view>
		</view>
	</view>
</template>
<script>
	export default {
		data() {
			return {
				//键盘高度
				keyboardHeight: 0,
				//底部消息发送高度
				bottomHeight: 0,
				//滚动距离
				scrollTop: 0,
				//发送的消息
				chatMsg: "",
				msgList: [],
				//当前用户的ID，也就是发送者的ID
				userId: 1,
				//对方用户的ID，也就是接收者的ID
				receiveId: 2,
				page: 1,
				size: 10,
				// senderName: "",
				// userAvatar:"",
				// senderAvatar:"",
				// senderContent:"",
				// userContent:""
			}
		},
		updated() {
			
			//页面更新时调用聊天消息定位到最底部
			this.scrollToBottom();
		},
		computed: {
			windowHeight() {
				return this.rpxTopx(uni.getSystemInfoSync().windowHeight)
			},
			// 键盘弹起来的高度+发送框高度
			inputHeight() {
				return this.bottomHeight + this.keyboardHeight
			}
		},
		onLoad(options) {
			this.userId = options.userId;
			this.receiveId = options.receiveId;
			this.getMsgList()
			// 页面加载时开始监听新消息
			// this.startListeningForNewMessages();
			// this.userId = options.userId

			uni.onKeyboardHeightChange(res => {
				//这里正常来讲代码直接写
				//this.keyboardHeight=this.rpxTopx(res.height)就行了
				//但是之前界面ui设计聊天框的高度有点高,为了不让键盘和聊天输入框之间距离差太大所以我改动了一下。
				this.keyboardHeight = this.rpxTopx(res.height - 30)
				if (this.keyboardHeight < 0) this.keyboardHeight = 0;
			})
		},
		onUnload() {
			uni.offKeyboardHeightChange()
			// 页面卸载时停止监听新消息
			this.stopListeningForNewMessages();

			// 取消请求
			// uni.request.abort()
		},
		methods: {
			focus() {
				this.scrollToBottom()
			},
			blur() {
				this.scrollToBottom()
			},
			// px转换成rpx
			rpxTopx(px) {
				let deviceWidth = wx.getSystemInfoSync().windowWidth
				let rpx = (750 / deviceWidth) * Number(px)
				return Math.floor(rpx)
			},
			// 监视聊天发送栏高度
			sendHeight() {
				setTimeout(() => {
					let query = uni.createSelectorQuery();
					query.select('.send-msg').boundingClientRect()
					query.exec(res => {
						this.bottomHeight = this.rpxTopx(res[0].height)
					})
				}, 10)
			},
			// 滚动至聊天底部
			scrollToBottom(e) {
				setTimeout(() => {
					let query = uni.createSelectorQuery().in(this);
					query.select('#scrollview').boundingClientRect();
					query.select('#msglistview').boundingClientRect();
					query.exec((res) => {
						if (res[1].height > res[0].height) {
							this.scrollTop = this.rpxTopx(res[1].height - res[0].height)
						}
					})
				}, 15)
			},
			// 发送消息
			handleSend() {
				//如果消息不为空
				if (!this.chatMsg || !/^\s+$/.test(this.chatMsg)) {
					let obj = {
						senderContent: this.chatMsg, // 添加了senderContent字段
						senderId: this.userId, // 修改了senderId的值
						titleId: 0,
						userContent: this.chatMsg,
						userId: this.userId,
						content: this.chatMsg, // 添加了content字段
						userAvatar: this.getUserAvatar(this.userId) // 获取用户头像的函数
					}
					this.msgList.push(obj);
					this.chatMsg = '';
					this.scrollToBottom()
					// 发送异步请求，将消息内容和其他信息发送给后端
					uni.request({
						url: 'http://localhost:8080/user/letter/send', // 后端的接口地址，根据实际情况修改
						data: {
							userId: this.receiveId, // 发送者的ID
							senderId: this.userId, // 接收者的ID
							content: obj.content // 消息内容
						},
						method: 'POST',
						success(res) {
							// 处理响应结果，比如提示发送成功或失败
							console.log(res.data);
						}
					})
				} else {
					this.$modal.showToast('不能发送空白消息')
				}
			},
			startListeningForNewMessages() {
				const _this = this
				// 创建一个定时器，每隔一秒钟发送一次请求
				this.intervalId = setInterval(() => {
					_this.getMsgList();
				}, 1000);
			},
			stopListeningForNewMessages() {
				// 清除定时器
				clearInterval(this.intervalId);
			},

			async getMsgList() {
				const _this = this

				// 发送请求
				const res = await uni.request({
					url: 'http://localhost:8080/user/letter/list',
					data: {
						userId: this.userId,
						senderId: this.receiveId
					},
					method: 'POST',
					success(res) {
						// 解析数据
						const {
							data: re
						} = res.data

						_this.msgList = re
						// console.log(_this.msgList);
						// console.log(_this.msgList);

						_this.msgList.forEach(item => {
							console.log(item);

							// 格式化时间戳
							item.createdTime = _this.formatDate(item.createdTime)
						})
					}
				})

				// 滚动到底部
				this.scrollToBottom()
			},
			getUserAvatar(userId) {
				console.log(userId);
				this.msgList.forEach(item => {
					// console.log(item);
					if (item.userId == userId) {
						console.log(item.userAvatar);
						return item.userAvatar
					}
				})
			},

			// 格式化时间戳
			formatDate(time) {
				const date = new Date(time)

				const y = date.getFullYear()
				const m = date.getMonth() + 1
				const d = date.getDate()

				const h = date.getHours()
				const min = date.getMinutes()
				const s = date.getSeconds()

				return `${y}-${m < 10 ? `0${m}` : m}-${d < 10 ? `0${d}` : d} ${h < 10 ? `0${h}` : h}:${min < 10 ? `0${min}` : min}:${s < 10 ? `0${s}` : s}`
			},

		}
	}
</script>
<style lang="scss" scoped>
	$chatContentbgc: #C2DCFF;
	$sendBtnbgc: #4F7DF5;

	view,
	button,
	text,
	input,
	textarea {
		margin: 0;
		padding: 0;
		box-sizing: border-box;
	}

	/* 聊天消息 */
	.chat {
		.scroll-view {
			::-webkit-scrollbar {
				display: none;
				width: 0 !important;
				height: 0 !important;
				-webkit-appearance: none;
				background: transparent;
				color: transparent;
			}

			// background-color: orange;
			background-color: #F6F6F6;

			.chat-body {
				display: flex;
				flex-direction: column;
				padding-top: 23rpx;
				// background-color:skyblue;

				.self {
					justify-content: flex-end;
				}

				.item {
					display: flex;
					padding: 23rpx 30rpx;
					// background-color: greenyellow;

					.right {
						background-color: $chatContentbgc;
					}

					.left {
						background-color: #FFFFFF;
					}

					// 聊天消息的三角形
					.right::after {
						position: absolute;
						display: inline-block;
						content: '';
						width: 0;
						height: 0;
						left: 100%;
						top: 10px;
						border: 12rpx solid transparent;
						border-left: 12rpx solid $chatContentbgc;
					}

					.left::after {
						position: absolute;
						display: inline-block;
						content: '';
						width: 0;
						height: 0;
						top: 10px;
						right: 100%;
						border: 12rpx solid transparent;
						border-right: 12rpx solid #FFFFFF;
					}

					.content {
						position: relative;
						max-width: 486rpx;
						border-radius: 8rpx;
						word-wrap: break-word;
						padding: 24rpx 24rpx;
						margin: 0 24rpx;
						border-radius: 5px;
						font-size: 32rpx;
						font-family: PingFang SC;
						font-weight: 500;
						color: #333333;
						line-height: 42rpx;
					}

					.avatar {
						display: flex;
						justify-content: center;
						width: 78rpx;
						height: 78rpx;
						background: $sendBtnbgc;
						border-radius: 8rpx;
						overflow: hidden;

						image {
							align-self: center;
							//实现头像自适应，且不变形
							width: 100%;
							height: 100%;
							object-fit: cover;
						}

					}
				}
			}
		}

		/* 底部聊天发送栏 */
		.chat-bottom {
			width: 100%;
			height: 177rpx;
			background: #F4F5F7;
			transition: all 0.1s ease;


			.send-msg {
				display: flex;
				align-items: flex-end;
				padding: 16rpx 30rpx;
				width: 100%;
				min-height: 177rpx;
				position: fixed;
				bottom: 0;
				background: #EDEDED;
				transition: all 0.1s ease;
			}

			.uni-textarea {
				padding-bottom: 70rpx;

				textarea {
					width: 537rpx;
					min-height: 75rpx;
					max-height: 500rpx;
					background: #FFFFFF;
					border-radius: 8rpx;
					font-size: 32rpx;
					font-family: PingFang SC;
					color: #333333;
					line-height: 43rpx;
					padding: 5rpx 8rpx;
				}
			}

			.send-btn {
				display: flex;
				align-items: center;
				justify-content: center;
				margin-bottom: 70rpx;
				margin-left: 25rpx;
				width: 128rpx;
				height: 75rpx;
				background: $sendBtnbgc;
				border-radius: 8rpx;
				font-size: 28rpx;
				font-family: PingFang SC;
				font-weight: 500;
				color: #FFFFFF;
				line-height: 28rpx;
			}
		}
	}
</style>